diff --git a/PHI-CL/control/inserter.lua b/PHI-CL/control/inserter.lua
index 4c513ef..97b3f27 100644
--- a/PHI-CL/control/inserter.lua
+++ b/PHI-CL/control/inserter.lua
@@ -69,20 +69,20 @@ function main.calc(entity)
     end
 
     if pickup_belt_speed and (stack_size > 1) then
-        ticks_per_cycle = ticks_per_cycle + main.get_belt_penalty(pickup_belt_speed * (entity.force.belt_stack_size_bonus or 1), stack_size)
+        ticks_per_cycle = ticks_per_cycle + main.get_belt_penalty(pickup_belt_speed, stack_size)
     end
 
     if drop_belt_speed and (stack_size > 1) then
-        ticks_per_cycle = ticks_per_cycle + main.get_belt_penalty(drop_belt_speed * (prototype.inserter_max_belt_stack_size or 1), stack_size)
+        ticks_per_cycle = ticks_per_cycle + main.get_belt_penalty(drop_belt_speed, stack_size)
     end
 
     if drop_belt_speed then
-        local max = drop_belt_speed * ticks_per_cycle * 4
+        local max = drop_belt_speed * ticks_per_cycle * 4 * (entity.force.belt_stack_size_bonus or 1)
         stack_size = (stack_size > max and max) or stack_size
     end
 
     if pickup_belt_speed then
-        local max = pickup_belt_speed * ticks_per_cycle * 8
+        local max = pickup_belt_speed * ticks_per_cycle * 8 * (prototype.inserter_max_belt_stack_size or 1)
         stack_size = (stack_size > max and max) or stack_size
     end